GREENVILLE, Miss. (Reuters) - Senator Elizabeth Warren, one of more than a dozen Democrats vying for the 2020 presidential nomination, on Monday called for the scrapping of the electoral college, the method used to elect U.S. presidents.

It was the first time Warren has explicitly called to eliminate the system established by the U.S. constitution, in which each state is allotted a set number of “electors” based on the combined total of the state’s representation in Congress.

Warren was participating in a televised CNN town hall in Jackson, Mississippi, when she was asked how, if elected, she would expand access to voting, including for those convicted of felonies.

Warren, 69, said there should be an amendment to the U.S. Constitution guaranteeing all citizens the right to vote, and called for the repeal of laws that make it more difficult to cast ballots.

She then lamented that White House candidates do not spend much time in places like Mississippi, which is conservative, and therefore not considered a swing state in U.S. presidential elections.

“Well, my view is that every vote matters. And the way we can make that happen is that we can have national voting. And that means get rid of the electoral college and everybody counts,” Warren said, eliciting some of the most enthusiastic applause of the night.

The electoral college has 538 electors and 270 are needed to win the presidency. Democrat Hillary Clinton won the popular vote in the 2016 presidential election but Republican Donald Trump won the electoral college.

Representative Steve Cohen of Tennessee introduced a constitutional amendment this year to eliminate the electoral college, but it has not been brought up for a vote in the House, which is controlled by Democrats.